Fix BGP's use of restart bit.

bgpd-restart-bit-fix.patch

ISSUE:

Quagga BGP doesn't send or use the restart-bit via the Graceful-Restart(GR)
capability. GR capability implementation isn't complete as per the RFC.

PATCH:

Patch uses BGP instance creation as the beginning of the startup period,
and 'restart_time' is taken as the startup period. As a result, BGP will
set the restart bit in the GR capability of the OPEN messages during the
startup period.

As an indication of quagga implementation's capability of sending End-Of-RIB,
helping a restarting neighbor, quagga BGP will now send global GR capability
irrespective of the graceful-restart config in BGP and the address-family
specific GR capability will be sent only if the GR config is present.
Forwarding bit is not set assuming its not preserved.

Incorporated feedback from David Lamparter via the quagga-dev mailing list.

Signed-off-by: Vipin Kumar <vipin@cumulusnetworks.com>
Reviewed-by: Pradosh Mohapatra <pmohapat@cumulusnetworks.com>
Reviewed-by: Paul Jakma <paul@opensourcerouting.org>
4 files changed